1. Technical Field of the Invention
The present invention relates generally to electrical lighters and more specifically to an electrical smoking lighter having a rotatable substrate in the shape of a disc or spiral bearing tobacco and further comprising suitable heaters and control logic.
2. Discussion of the Related Art
Previously known conventional lit cigarettes deliver flavor and aroma to the user as a result of combustion of tobacco. A mass of combustible material, primarily tobacco, is oxidized as the result of applied heat with typical combustion temperatures in a conventional lit cigarette being more than 800.degree. C. during puffing. Heat is drawn through an adjacent mass of tobacco by drawing on the mouth end. During this heating, inefficient oxidation of the combustible material takes place and yields various distillation and pyrolysis products. As these products are drawn through the body of the lit cigarette toward the mouth of the smoker, they cool and condense to form an aerosol or vapor that gives the consumer the flavor and aroma associated with smoking.
Conventional lit cigarettes have various perceived drawbacks associated with them. Among them is the production of sidestream smoke during smoldering between puffs, which may be objectionable to some non-smokers. Also, once lit, they must be fully consumed or be discarded. Relighting a conventional cigarette is possible but is usually an unattractive prospect for subjective reasons (flavor, taste, odor) to a discerning smoker.
A prior alternative to the more conventional lit cigarettes includes those in which the combustible material itself does not directly provide the flavorants to the aerosol inhaled by the smoker. In these lit cigarettes, a combustible heating element, typically carbonaceous in nature, is combusted to heat air as it is drawn over the heating element and through a zone that contains heat-activated elements that release a flavored aerosol. While this type of lit cigarette produces less sidestream smoke, it still generates products of combustion, and once lit it is not adapted to be snuffed for future use in the conventional sense.
In both the more conventional lit cigarettes and lit carbon element cigarettes described above combustion takes place during their use. This process naturally gives rise to many by-products as the combusted material breaks down and interacts with the surrounding atmosphere.
Several proposals have been advanced which significantly reduce undesired sidestream smoke while permitting the smoker to suspend smoking of the cigarette for a desired period and then to resume smoking. Commonly assigned U.S. Pat. Nos. 5,093,894; 5,225,498; 5,060,671 and 5,095,921 disclose various electrical resistive heating elements and flavor generating systems which significantly reduce sidestream smoke while permitting the smoker to selectively suspend and reinitiate smoking. Alternatively, semiconductor heaters, such as those described in copending, commonly assigned U.S. patent application Ser. No. 07/943,505, filed Sep. 11, 1992 and hereby incorporated by reference in its entirety, can be used. Additional heater configurations are also disclosed in application Ser. No. 07/943,505, as well as in copending, commonly assigned U.S. patent application Ser. No. 07/943,504, filed Sep. 11, 1992 and hereby incorporated by reference in its entirety.
These replaceable heater/flavor units contain a limited number of individual charges of tobacco, and thus provide a limited number of portions or puffs of tobacco flavors to the smoker. For example, a heater/flavor unit of the type described above might provide eight or ten puffs as provided by a more conventional lit cigarette. The smoker would be required to continually change heater/flavor units throughout a day of using the electrical lighter. Each time the heater/flavor unit is changed, additional wearing of the contacts on the permanent portion of the lighter occurs. Also, each spent heater/flavor unit increases the volume of material to be disposed.
U.S. Pat. No. 5,388,594, issued Feb. 14, 1995, U.S. patent applications Ser. No. 08/380,718, filed Jan. 30, 1995; Ser. No. 08/425,166, filed Apr. 20, 1995, entitled "Cigarette for Electrical Smoking System" (Attorney Docket No. PM 1759A); Ser. No. 08/425,837, filed Apr. 20, 1995, entitled "Cigarette for Electrical Smoking System" (Attorney Docket No. PM 1759B); and Ser. No. 08/426,165, filed Apr. 20, 1995, (Atty. Docket No. PM 1768) describe novel electrically powered lighters and novel cigarettes adapted to cooperate with the lighter. The preferred embodiment of the lighter of U.S. Pat. No. 5,388,594 includes a plurality of metallic sinusoidal heaters disposed in a configuration that slidingly receives a tobacco rod portion of the cigarette. One of the many advantages is the reusability of the lighter for numerous cigarettes.
In the above noted electrical smoking systems, the cigarette is manually removed from the lighter by the smoker. Relatively tight interfaces between the cigarette and heater blades, e.g., inwardly biased blades, are desired for good thermal transfer to the cigarette, but may require a forceful pulling by the smoker to withdraw the cigarette, potentially damaging the heater assembly, electrical connections, etc. Also, this withdrawal could possibly break the thermally weakened cigarette, thereby complicating, if not frustrating, cigarette removal and potentially leaving cigarette remnants in the lighter which may block insertion of subsequent cigarettes or affect subjective qualities of subsequently smoked cigarettes.
The lighter described in the incorporated application Ser. No. 08/105,346 comprises a tobacco containing web enclosed in a cassette casing for registry with a heating configuration via a web advancing mechanism. This lighter provides a significant number of puffs without the need for replacement and avoids excessive trauma to heater elements. However, it would be desirable to provide a more sound tobacco carrier than a web which may potentially be subject to uneven tensioning and, perhaps, complete failure, especially after heating.
As with any widely used consumer product, it would also be desirable to reduce the amount of disposable components of any electrical lighter. For example, it would be desirable to limit required disposal of a used component to a convenient time, e.g., once per day. Also, it would be desirable to provide a supply of tobacco for an electrical lighter which is easily inserted and removed from the lighter. It would also be desirable to provide a replaceable flavor or heater/flavor unit for such an electrical lighter.